[Effects of ischemic preconditioning on the oxidative stress in small bowel autotransplantation]

One determining factor in intestinal transplantation is the bowel's extreme sensitivity to ischemia-reperfusion injury. This study was meant to investigate the effect of ischemic preconditioning prior to autotransplantation. Total orthotopic intestinal autotransplantation was performed in 40 mongrel dogs. Four groups (GI-GIV) were established. In GI and GII grafts were stored in 4 degrees C Euro Collins and University of Wisconsin solutions. In GIII and GIV before preservation IPC was induced by 4 cycles (5-min ischemia + 10-min reperfusion). Three hours of preservation was followed by 1 hour of reperfusion. We determined oxidative stress markers in bowel tissue [reduced glutathione (GSH), superoxide dismutase (SOD)], oxygen free radicals (OFRs) (confocal microscopy), NF-kappa B (gel electrophoretic mobility shift assay), DNA damage (TUNEL). Cold preservation could not prevented against oxidative stress and resulted decrease of SOD activity significantly during reperfusion. In the preconditioned groups the elevated GSH and better preserved SOD activity indicated development of protection. Production of OFRs increased during reperfusion in non-preconditioned groups. Activation of NF-kappa beta was peaking by 1-3 hours following preconditioning. We detected more cells suffered DNA strand breaks in preconditioned groups. Our findings confirm that ischemic preconditioning prior to preservation can moderate the severity of oxidative stress and activate the endogenous celluar adaptation in bowel tissue.